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Acyclic Carboxylic acids Card 1

2-methyl-2-butenoic acid

Build order

  1. 1Find the principal suffix
  2. 2Choose the parent chain or ring
  3. 3Number from the suffix end
  4. 4Place C=C and C≡C
  5. 5Add groups and branches
  6. 6Check repeated locants
  7. 7Fill H by valence

Bond-line

MarkMeansDraw
End / cornerCarbonDo not label C
—Single bondTap once
=Double bondTap bond again
≡Triple bondTap bond again
Branch lineCarbon branchStart at its locant
OOxygen atomNever read as OH
OHHydroxylPlace OH explicitly
Unshown HImplicit hydrogenComplete valence last

Valence

AtomUsual totalCheck
C4single 1, double 2, triple 3
N3amine pattern
O2carbonyl O has one double bond
H1fill after the skeleton
F, Cl, Br, I1one bond
carbonslocantsbondsvalenceone molecule

Functional priority

#GroupStructurePrefixSuffixDrawing rule
1Carboxylic acid
-COOH
carboxy--oic acid / -carboxylic acidCOOH carbon is C1
2Acid anhydride
-CO-O-CO-
--oic anhydrideName from parent acid
3Ester
-COOR
alkoxycarbonyl--oate / -carboxylateAlkyl side first
4Amide
-CONH2
amido--amide / -carboxamideN-substituents use N-
5Nitrile
-C≡N
cyano--nitrile / -carbonitrileNitrile carbon counts in chain
6Aldehyde
-CHO
oxo--al / -carbaldehydeCHO carbon is C1
7Ketone
>C=O
oxo--oneGive C=O lowest locant
8Alcohol
-OH
hydroxy--olGive OH lowest locant
9Amine
-NH2
amino--amineGive NH2 lowest locant
10Alkene
C=C
enyl--eneLowest multiple-bond locant
11Alkyne
C≡C
ynyl--yneLowest multiple-bond locant
12Alkane
C-C
alkyl--aneBase hydrocarbon

Numbering

  1. 1Parent contains the highest-priority group and as many multiple bonds as possible.
  2. 2Give the principal suffix the lowest locant.
  3. 3Then minimize C=C / C≡C; then substituents.
  4. 4COOH, CHO, CONH2 and CN suffix carbons count in the parent when applicable.
  5. 52-ene means C2=C3; 2-yne means C2≡C3.
  6. 6Add substituents only after the numbered parent is fixed.
  7. 7Use di-, tri-, tetra- with every locant.
  8. 8Alphabetize different substituents; ignore di-, tri-, tetra-.
  9. 9A ring suffix carbon is normally C1.
  10. 10Phenol: OH carbon C1. Benzoic acid: COOH-bearing ring carbon C1.

Parent roots

1methmethane / methyl 2ethethane / ethyl 3proppropane / propyl 4butbutane / butyl 5pentpentane / pentyl 6hexhexane / hexyl 7heptheptane / heptyl 8octoctane / octyl 9nonnonane / nonyl 10decdecane / decyl

Groups and endings

Prefixes

GroupPrefix
F / Cl / Br / Ifluoro- / chloro- / bromo- / iodo-
-NO2nitro-
-CH3methyl-
-CH2CH3ethyl-
-C6H5phenyl-
-OHhydroxy- when not principal
-NH2amino- when not principal
>C=Ooxo- when not principal

Skeleton to ending

StructureEnding
C-C-ane
C=C-ene
C≡C-yne
-OH-ol
>C=O-one
-CHO-al
-COOH-oic acid
-CONH2-amide
-COOR-oate
-C≡N-nitrile

Rings and special forms

PatternNumbering / constructionExample
CycloalkanoneCarbonyl ring carbon is C12-bromo-5-methylcyclohexanone
PhenolOH-bearing carbon is C12,4-dibromophenol
Benzoic acidCOOH-bearing ring carbon is C12,4-dichlorobenzoic acid
PyridineRing N is position 13-bromopyridine
Benzene relation1,2 ortho   1,3 meta   1,4 paraUse locants in systematic names
AmideR-C(=O)-NH2; N- replaces an H directly on NN-methylpropanamide
EsterO-side alkyl first; acid-derived alkanoate secondethyl ethanoate
Amine with higher suffixUse amino- as a prefix1-amino-2-methyl-1-phenylpropane
Nonprincipal carbonylUse oxo-3,4-dioxopentanal

Decoded examples

2-methylbut-2-enoic acid

COOH C14 carbonsC2=C3CH3 at C2

5-chloro-3-ethylhex-4-en-2-ol

6 carbonsOH C2C4=C5ethyl C3Cl C5

4-chloro-5-nitro-6,6-diiodo-7-methylnon-2-yne

9 carbonsC2≡C3Cl C4NO2 C5I, I C6CH3 C7

2,4-dibromophenol

OH carbon C1Br C2 and C4

N-methylpropanamide

CH3CH2CONHCH3replace one N-H with CH3

1-amino-2-methyl-1-phenylpropane

propaneNH2 C1phenyl C1CH3 C2

2-bromo-5-methylcyclohexanone

carbonyl C1Br C2CH3 C5

3,4-dioxopentanal

CHO C15 carbonsC=O at C3 and C4

3-bromopyridine

ring N position 1Br C3

ethyl acetate / ethyl ethanoate

CH3COOCH2CH3ethyl on O-sideethanoate on carbonyl side

2,4-dichlorobenzoic acid

COOH-bearing ring carbon C1Cl C2 and C4